With Elisa Maggio and Adriano Frattale-Mascioli we looked at the detected gravitational waves populations as if composed of exotic compact objects.

Exotic compact objects (ECOs) are proposed alternatives to black holes (BHs) that can mimic their behaviours while removing the event horizon. However, ECOs are subject to ergoregion instability; namely, if their spin is too high, they are unstable. We infer that no more than 20% of the compact objects could be ECOs by looking at the spin distribution of detected GW sources. We also demonstrate that the Einstein Telescope will obtain far better results with just a few days of data-taking.

Please, feel free to read our paper and reach out to us for any question or suggestion.

Title: Limits on the existence of totally reflective exotic compact objects with current and future gravitational-wave detectors

Authors: S. Mastrogiovanni, E. Maggio, A. Frattale-Mascioli

Figure: Upper limits on the fraction of ECOs as function of the compactness (position of the ECO’s surface from the would-be event horizon).